DragonFly kernel List (threaded) for 2004-08
Re: DragonFlyBSD for embededd system...
:Who compare DragonFlyBSD kernel with QNX kernel?
:Interestin read article about comare DragonFlyBSD kernel with QNX kernel
Well this sounded interesting so I did a google search and found a
number of good comments, but no real articles comparing the abstractions
used by the two. It does seem that people 'outside' our developer
forums really *DO* understand what DragonFly is trying to do, which is
I found comments from people describing DragonFly as a Hyrbid-OS (hybrid
between monolithic and pure messaging), and that is 100% correct.
I think we have already demonstrated that judicious use of messaging
and threads to break up major subsystems results in a HUGELY simplified
programming model (especially when it comes to concurrency) without
necessarily sacrificing performance. We haven't even *tried* to
optimize what we've done so far with the network stack, and yet Jeff
has managed to thread nearly the entire thing with virtually no sacrifice
in performance vs FreeBSD-4, and the code is like 95% of the way towards
MP safeness in regards to being able to turn off the BGL for those
threads. Not only that but we have already been able to leverage the
model in very simple ways to implement things that make a real difference
with regards to Gigabit performance.
Our ability to turn off the Big Giant Lock in a major subsytem is going
to be an important milestone for us, and we are very close now to being
able to do it in the network subsystem.